Pass '/' as an argument to home_url(), preventing possible 404.
Pass '/' as an argument to home_url(), preventing possible 404.

In response to a support topic,
where the link wrapping the home logo in
legacy templating lead to a 404 page.
According to the documentation for home_url(),
passing the '/' argument is the default usage.
@see https://wordpress.org/support/topic/need-to-add-slash-to-end-of-url/#post-10293713

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